This is a working overview of Semax, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-12-18 and is reviewed periodically as new material appears.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
| Property | Value | Notes |
|---|---|---|
| Appearance | White lyophilized powder | Typical for synthetic peptides |
| Solubility | Freely soluble in water | Also soluble in saline |
| Storage temperature | -20 C or below | Protect from repeated freeze-thaw |
| Analytical method | Reverse-phase HPLC | Confirms purity and identity |
| Common synonym | ACTH(4-10) analog | Reflects structural origin |
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
== Side effects == Miconazole is generally well tolerated. The oral gel can cause dry mouth, nausea and an unpleasant taste in about 1–10% of people. Anaphylactic reactions are rare. The drug prolongs the QT interval.
The formula (6) and (7) give a direct relation between the secular frequency and the digital drive waveform parameters (frequency and amplitude), without using the iterative process that is needed for a sinusoidal driven quadrupole ion trap. Normally the depth of the 'effective potential' well, or the pseudopotential well, is used to estimate the maximum kinetic energy of ions that remain trapped. For DIT, this was also derived using Dehmelt approximation:
The game remained in PC Data's weekly top 10 until the week of March 21 and dropped to position 11 for March as a whole. In the United Kingdom, it placed second in February—behind the debut of Baldur's Gate—and fifth in March. In April, it claimed #3 on Chart-Track's rankings and dropped to #16 on those of PC Data. On April 23, Sierra announced that global sales of Half-Life had reached almost 1 million copies. After maintaining the 16th place for May in the U.S., Half-Life exited PC Data's monthly top 20 in June. Half-Life became the fifth-best-selling PC game of the first half of 1999 in the U.S. Its domestic sales during 1999 reached 290,000 copies by the end of September. During 1999, it was the fifth-best-selling PC game in the U.S., with sales of 445,123 copies. These sales brought in revenues of $16.6 million, the sixth-highest gross that year for a PC game in the U.S. The following year, it was the 16th-best-selling PC game in the U.S., selling another 286,593 copies and earning $8.98 million. Half-Life dominated FPS sales of the period. Robert M. Atkins, the design lead of the FPS Sin, released shortly before Half-Life, said: "Half-Life just crushed the market. It completely changed the first-person shooter narratives." The PlayStation 2 version received a "Silver" sales award from the Entertainment and Leisure Software Publishers Association (ELSPA), indicating sales of 100,000 copies in the UK Half-Life's global sales reached 2.5 million copies by July 2001.
Affinity towards An(III) over Ln(III) Good An(III) back-extraction to enable solvent recycling Good solubility in a proper diluent CHON compliance to reduce secondary waste Fast complexation kinetics Hydrodynamic stability to prevent third phase and precipitates formation during extraction process Chemical and radiolytic stability to prevent solvent degradation Research on advanced reprocessing of spent nuclear fuel moves on by developing process optimization studies and designing new potential lipophilic and hydrophilic extracting agents that fulfill these industrial requirements.
Sources: en.wikipedia.org
== History == Paniz-Mondolfi was born in Caracas, Venezuela in 1976. His mother is a pediatrician and his father an architect. His grandfather, Edgardo Mondolfi Otero, a biologist and zoologist. Two of his uncles were physicians with special ambitions in the field of sciences and research. His childhood was shared between Caracas and Kenya. Paniz-Mondolfi has a master's degree in parasitology and tropical diseases; he did international fellowships in microbiology, molecular genetics, and skin disease. He also did a second medical residency in the United States in pathology. He isolated and described a new species of parasite that had infected a NY resident, and a new mycobacterium that sickened two people in Connecticut. He earned an MD and PhD and studied under Jacinto Convit the leprosy researcher. He was a pathologist at the IDB Biomedical Research Institute in Barquisimeto, Venezuela until 2019 when he fled to the United States. He is the founder of the Venezuelan Science Incubator, an independent health research organization. Paniz-Mondolfi is assistant professor of pathology, molecular and cell-based medicine at the Mount Sinai Icahn School of Medicine. He is also affiliated with the Yale Cancer Center. In 2020 he focused his research on the COVID-19 pandemic and the effects the virus had on minority children. His research findings have been published in several medical journals including: the European Society of Clinical Microbiology and Infectious Diseases, The American Association for the Advancement of Science, and The Lancet.
== Examples == The diabetic drug Liraglutide, incorporates a lipid chain to extend plasma circulation and prolong bio-availability. Liraglutide is a GLP-1 agonist drug that self-assembles into an alpha-helical structure, and it requires once a day administration. Lipid conjugation of a palmitoyl chain to a lysine residue at position 26 of Liraglutide results in an extended half-life (around 13–14 hours) in the blood. This is due to the palmitoyl chain allowing non covalent binding to albumin, which delays proteolytic attack by DPP IV and also rapid renal clearance. Furthermore, the addition of the lipid chain could further prolong half-life by sterically hindering the DPP IV enzyme from degradation. Another peptide known to self-assemble is the octapeptide Lanreotide. This compound is a synthetic analogue of the peptide hormone somatostatin and it is used to treat acromegaly (a condition where the body produced too much growth hormone). In water, Lanreotide self-assembles into monodisperse liquid crystalline nanotubes. The nanotubes are made up of dimers that self-assemble into a 2D crystal, which is held together by lateral chain interactions, and also by anti-parallel ß-sheets. Further insight into how self-assembly and peptide hormones are related has been provided by studies on self-assembling amyloid structures formed by peptide hormones and neuropeptides. Peptide hormones and neuropeptides form dense-cored aggregates that pack into dense-core vesicles (DCVs), which are used to temporarily store peptide messengers in secretory cells.
Post-SSRI sexual dysfunction (PSSD) is an iatrogenic condition in which sexual side effects persist after discontinuation of serotonin reuptake inhibiting antidepressants, including sertraline. Characteristic symptoms include genital numbness, pleasureless or weak orgasm, loss of libido, and erectile dysfunction; non-sexual symptoms such as emotional blunting and cognitive impairment may also occur. The condition can arise after even brief exposure to a serotonin reuptake inhibitor and may persist indefinitely; there is currently no established treatment. The DSM-5 noted in 2013 that serotonin reuptake inhibitor-induced sexual dysfunction may persist after the agent is discontinued. The UK's Medicines and Healthcare products Regulatory Agency received its first report of a sexual dysfunction persisting after an SSRI was stopped — involving fluoxetine — in 1991, and sertraline has been among the SSRIs most frequently implicated in subsequent reports. A 2023 retrospective cohort study of over 12,000 males estimated the risk of irreversible sexual dysfunction at approximately 0.46% of patients treated with serotonergic antidepressants, including SSRIs, though the actual prevalence remains uncertain and the condition is likely underreported. A 2023 systematic review found that nearly every SSRI currently marketed has been associated with reports of PSSD, with escitalopram, citalopram, paroxetine, sertraline, and fluoxetine accounting for the majority of reported cases.
Sources: en.wikipedia.org
Dualism A philosophical position asserting that the mind and body are fundamentally distinct entities. In neuroscience, it contrasts with monistic and physicalist views of consciousness. Dynein A motor protein that moves along microtubules in the cytoskeleton, transporting cellular cargo toward the center of the cell. In neurons, dynein is important for retrograde axonal transport. Dysarthria A motor speech disorder resulting from impaired control of the muscles used in speech, often due to neurological damage to the brainstem or cerebellum. Dyskinesia Involuntary, erratic, or repetitive movements, often associated with long-term use of dopaminergic drugs in Parkinson’s disease. Dyslexia A neurodevelopmental disorder characterized by difficulty with accurate and/or fluent word recognition, often linked to deficits in phonological processing and left hemisphere brain function. Dyspraxia A developmental coordination disorder involving difficulty with motor planning and execution, affecting balance, fine motor tasks, and speech.
=== EC 1.5.1 With NAD+ or NADP+ as acceptor === EC 1.5.1.1: 1-piperideine-2-carboxylate/1-pyrroline-2-carboxylate reductase (NAD(P)H) EC 1.5.1.2: pyrroline-5-carboxylate reductase EC 1.5.1.3: dihydrofolate reductase EC 1.5.1.4: Now included with EC 1.5.1.3 dihydrofolate reductase EC 1.5.1.5: methylenetetrahydrofolate dehydrogenase (NADP+) EC 1.5.1.6: formyltetrahydrofolate dehydrogenase EC 1.5.1.7: saccharopine dehydrogenase (NAD+, L-lysine-forming) EC 1.5.1.8: saccharopine dehydrogenase (NADP+, L-lysine-forming) EC 1.5.1.9: saccharopine dehydrogenase (NAD+, L-glutamate-forming) EC 1.5.1.10: saccharopine dehydrogenase (NADP+, L-glutamate-forming) EC 1.5.1.11: D-octopine dehydrogenase EC 1.5.1.12: Now EC 1.2.1.88, L-glutamate γ-semialdehyde dehydrogenase EC 1.5.1.13: Now EC 1.17.1.5, nicotinate dehydrogenase EC 1.5.1.14: Now included with EC 1.5.1.21 Δ1-piperideine-2-carboxylate reductase EC 1.5.1.15: methylenetetrahydrofolate dehydrogenase (NAD+) EC 1.5.1.16: D-lysopine dehydrogenase EC 1.5.1.17: alanopine dehydrogenase EC 1.5.1.18: ephedrine dehydrogenase EC 1.5.1.19: D-nopaline dehydrogenase EC 1.5.1.20: methylenetetrahydrofolate reductase (NAD(P)H) EC 1.5.1.21: 1-piperideine-2-carboxylate/1-pyrroline-2-carboxylate reductase (NADPH) EC 1.5.1.22: strombine dehydrogenase EC 1.5.1.23: tauropine dehydrogenase EC 1.5.1.24: N5-(carboxyethyl)ornithine synthase EC 1.5.1.25: thiomorpholine-carboxylate dehydrogenase EC 1.5.1.26: β-alanopine dehydrogenase EC 1.5.1.27: 1,2-dehydroreticulinium reductase (NADPH) EC 1.5.1.28: opine dehydrogenase EC 1.5.1.29: Now covered by EC 1.5.1.38 [FMN reductase (NADPH)], EC 1.5.1.39 [FMN reductase [NAD(P)H])] and EC 1.5.1.41 (riboflavin reductase [NAD(P)H]) EC 1.5.1.30: flavin reductase (NADPH) EC 1.5.1.31: berberine reductase EC 1.5.1.32: vomilenine reductase EC 1.5.1.33: pteridine reductase EC 1.5.1.34: 6,7-dihydropteridine reductase EC 1.5.1.35: identical to EC 1.2.1.19, aminobutyraldehyde dehydrogenase, as the substrates 1-pyrroline and 4-aminobutanal are interconvertible EC 1.5.1.36: flavin reductase (NADH) EC 1.5.1.37: FAD reductase (NADH) EC 1.5.1.38: FMN reductase (NADPH) EC 1.5.1.39: FMN reductase (NAD(P)H) EC 1.5.1.40: 8-hydroxy-5-deazaflavin:NADPH oxidoreductase EC 1.5.1.41: riboflavin reductase (NAD(P)H) EC 1.5.1.42: FMN reductase (NADH) EC 1.5.1.43: carboxynorspermidine synthase EC 1.5.1.44: festuclavine dehydrogenase EC 1.5.1.45: FAD reductase (NAD(P)H) EC 1.5.1.46: agroclavine dehydrogenase EC 1.5.1.47: dihydromethanopterin reductase [NAD(P)+] EC 1.5.1.48: 2-methyl-1-pyrroline reductase EC 1.5.1.49: 1-pyrroline-2-carboxylate reductase [NAD(P)H] EC 1.5.1.50: dihydromonapterin reductase EC 1.5.1.51: N-[(2S)-2-amino-2-carboxyethyl]-L-lutamate dehydrogenase EC 1.5.1.52: staphylopine dehydrogenase EC 1.5.1.53: methylenetetrahydrofolate reductase (NADPH) EC 1.5.1.54: methylenetetrahydrofolate reductase (NADH)
== Structure == Serous membranes have two layers. The parietal layers of the membranes line the walls of the body cavity (pariet- refers to a cavity wall). The visceral layer of the membrane covers the organs (the viscera). Between the parietal and visceral layers is a very thin, fluid-filled serous space, or cavity.
Dehydration is a common risk factor for exertional rhabdomyolysis because it causes a reduction of plasma volume during exertion. This leads to a reduction of blood flow through the vascular system which inhibits blood vessel constriction.
Sources: en.wikipedia.org
It is associated with the melanocortin receptor family, particularly subtypes found in the central nervous system. This interaction is separate from the adrenal pathway activated by full-length ACTH.
Peptidases degrade the compound within minutes in circulation. This short half-life is one reason nasal delivery is used, placing the substance close to the olfactory and trigeminal pathways.
No large multicenter trials have been published in English-language journals. The existing human evidence consists mainly of smaller studies conducted in Russia, which limits generalization.
It is a synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.